Thousands of Vietnamese Catholics have filled the streets of the capital to witness the ordination of 57 new priests in a service presided over by a Vatican representative. The unprecedented ceremony shows a thaw in relations between the Roman Catholic Church and Vietnam's communist government.

The sound of ancient Latin has been a part of the Roman Catholic Church for centuries, but for the Vietnamese worshippers who packed the streets outside St. Joseph's Cathedral in Hanoi the chants had a new significance. For the first time in communist Vietnam, the Mass inside was conducted by a representative of the Vatican.

Cardinal Crescenzio Sepe presided over the ordination of 57 new priests from eight northern Vietnam dioceses, the largest number ever ordained in the country at one time.

The new priests prostrated themselves in front of Cardinal Sepe for 20 minutes in the elaborate ceremony, then rose to be blessed by him and two Vietnamese cardinals. The crowds of worshippers cheered when the Vatican representative relayed greetings from Pope Benedict XVI and quoted the late Pope John Paul II as saying, "Vietnam is always in my heart."

Tuesday's service marked a new level of cooperation between the Catholic Church and Vietnam's communist government.

Vietnam has six million Catholics, the second largest number in Southeast Asia after the Philippines.

Ordinary worshippers face few restrictions in practicing their faith, but relations between the communist government in Hanoi and the Vatican have been strained over who controls church leadership and the jailing of dissident priests.

There are no diplomatic relations between the Vatican and Hanoi, and Vietnam's government limits the number of priests-in-training admitted to seminaries. The government also insists on the power to appoint bishops, a right the Vatican says belongs to the pope alone.

But relations have improved in recent years. Hanoi sent a delegation to the Vatican in June and agreed to allow more priests to be trained.

In February, the government also released Father Nguyen Van Ly from prison. Father Ly had been serving a 15-year sentence for "undermining national unity" after he publicly criticized the government.

It is unclear whether the ordinations will lead to Vietnam and the Vatican establishing diplomatic relations. But for Vietnamese Catholics, the prospect of peace between their church and their state is something worth praying for.